针对高砷地下水的强化除砷技术优化及效能研究

Optimization and Performance of Technology to Remove Arsenic from Groundwater

利用中试研究了针对内蒙古某水厂高砷地下水的除砷技术方案，并优化了其工艺参数，初步确定了其除砷效能。结果表明，针对当地地下水水质特征，其基本除砷方案宜采用投加除砷药剂反应后进行过滤的方法。其中，除砷药剂宜采用氯化铁与高锰酸钾的复合药剂，其配比（以铁和高锰酸钾的质量计）采用4：1；除砷药剂投加后的反应时间宜控制在2min左右；采用锰砂与石英砂的双层过滤单元，滤层总厚度不小于1．0m，其中锰砂厚度宜大于30cm，且滤速控制在5～7m／h为宜。针对优化后工艺参数的长期验证试验结果表明，出水的砷、锰含量分别稳定在5μg／L和0．05mg／L以下。

Pilot tests were used to optimize the parameters of the process for arsenic removal from the groundwater in a waterworks in Inner Mongolia, and the performance of the optimized scheme was tes- tified in the meantime. The results showed that the optimized scheme for the arsenic removal in the re- search site was adding agents, reaction a little while and then filtration in sequence. The agent for the ar- senic removal should be composed of ferric chloride and potassium permanganate as a mass ratio of 4 ： 1 （ Fe ： KMnO4 ）. The reaction time of the agent was about 2 min. The filtration was performed with man- ganese sand and silica sand. The total depth of the filter layer should be equal to or more than 1.0 m, in which the depth of manganese sand should be more than 0.3 m, and the filtration velocity should be be- tween 5 to 7 m/h. The contents of As and Mn in the effluent were below 5 μg/L and 0.05 mg/L respec- tively.